Work-holding means



Feb. 15, 1927.

' woRx HOLDING MEANS- vFiled Aug. 13, 1925y liu mij n F. A. BAILYIEY` l y Patented` Feb. 15, 1927.

FRANK A. BAILEY, `or-TOLEDO,.o1-rio,Assiefivoza 'ioV rim DEV'VILBISSMANUFAGTURING COMPANY, or TOLEDO, 01110, ,AcoRronArrioN AOron-ro, e f

WoRnfHoLDiNe MEANS.

-Applicatouled f August 13, 1925. Serial .No. 50,0816.

This invention relates-'to means 'for holding a work-piece -ywhile being operatedon, fand which, in the'fpresentcase, is adapted at the saine 'time to impart rotary movement to the worln The object of the invention is theprovi- -sioii'of simple,eificient and novel means,

lwliich'isoperablefto securely liold an: article to a carrying-part1by'suctionand is also operable vto effect avrelease of the article.

'A Vfurther ebject of the invention gis the provision, -in combination with -arrotatable work-holder or spindle, of unitary means ifor controlling the 'rotation yoi? Athe work? holder Vand tlieliol'ding of the work thereto.

iFurther objects and advantages of the invention will be -apparent from the fiollow lingA detailedv description i thereof.

-/Vhile the invention in its broader aspect is capable of' embodiment innumerous forms,

one embodimentv thereofA is illustrated in the accompanying drawings,-in wliiclif;

Figure l isa/side elevation of anapparatusiembodyingjtliefinvention with parts in isectioii, Aand AFig 92 is an 'enlarge'dzsectional detail ofthe aircontrol means.

Referring tothe drawings, l designates a frame having vertically -aligned2bearings 2' and?) therein for -a 'spindle or shaft 4, to which, in thepresent-instance, intermediate *the `bearings 'is secured a ffrietie'n wheel 5. lOn the lupper'end yo'f'tlie shaft 4 above the bearing 3 is seeureda cylindrical shell (hav-V ing a plunger ,7 mounted for' reciprocatory movementstherein and -iinpelled to Ihave Y inward movement therein'byj'a coiled-expansion vspring 8 ,disposed between fthe plunger and the outer end o'ii'lthe cylinder. Astem "9 vprojects axially ffrom the outerend of rthe cylinder shell andf has 'a passagei throughout, v"its length which communicates at its innerend with "th'einterior o'fkthe cylinder.

.A rubber disc or'cup A10 is -securedltothe outer end offthe stemlfor rotation 'therewith 'and isintended to lit at its edge lportion* closely against an article yor yworlcpiece "a,

I'to `firmly hold it to the Y' cup for rotation therewith when a vacuumory suction action isc-reated through'the stem"9-by reason of an inward'movement of the plunger 7. rThe cylinder 6 is'enlarged with respect to the sha'ft14 and has a thrustbearinglllbetween lits innerend andvthe'bearing 3.

4Ai'ruiideipressureis admitted tothe cyl force the plunger outward against-dietenoi" suction V.action on y the. article a, and this air is introducedintofthe cylinderthrough a passage '12 provided V'axially tlirou-gli the shaft 4. -A'tube Y13 fis fiiirstuifing-boxcon- Y `sion of tlie'spring Sto release'theholdingl nection at one end =with"theouter fend oftlie `shaft 4 andhas its other eiidfinf communica Ation with a -valve-chamber14;,provided:in

a frame partei' block 15g-The chamber Y1'4 chamber `14 is also incoininunicationwvith an exhaust passage'li) and such communication is `normally"closedV by a valveA 20 `which is 'held seated by aspiing l21.-,'and hasgafstem 22projecting from an end1ofrthe'bloclc15. The' communicati'oii"between the supply `chamber' -17 rand .passage '116 is knorinally closed Vby a fvalvex2'3, 'which Visaseated' by a spring 124, and' hasV stem' 25,v proj ecting from the 1 same end-1 of the vblock: as the ivfalve :stein 22. Itis :evident .that 'an inward `movement on either valve stems22 `or 25 willz'eflectan unseating of' the; associated valve.

Ailever 26 is 'fulcrumedtof-the end ofthe block 15, fremiwhicli-the 1valve stems A22-and 25 fproject, and :has one Aarrnn` engagement "with lone lvalvewstein and sitsotlier -arm in enga gement withi the other ivalve';y stem-where Abyvaninvvardro'ckingxof the lower'farm ofY .the iflever, in lthe present winstanee, vetects .anopening of the supply 'valveLQ/B and per- -mits 'a closing of 'the exhaust vale 20, 'and A rol-ler :.27 V:is carried4 by athe lower'endportion ofathe lever Qhand rides vice versa.

so' y on the .periphery ofvafeain 28 `.fixed en a l' shaft 1j ournalled in. an farm 30"0f1' the lframe y' y1. [An armBLIi-Xedly projects'ronrthegcamshaft? 29 andhas; a link orirodvconiiection 32 with any suitable foot pedal'oramanual'oper-V ating .means, which, 1in the xp'resent instance, :may comprise the footpiece 83 onzthe lower 'end-of thenconnection. lYIlieaarnfiBl isfnorinally held elevated, .whicliis accomplished,

initlie present`instance,by yavspringf`34. A Aspring .actsfonithe lever 26toiretain its roller 27.in :contact withthe camyperipli'ery. When thel control iarm 31 z is in' its fnormal raised position, shown .in iFig.v 1,1tlierlever Yroll'Qffrests in iaxdepression '36in zthe Aperipliery of th'e'f cani; 2.8? andv .p ermits the .f lever 26to stand in `positioirto efectzanqopening ef-fthezealiaust aalvea()andapsrmim clcsng of the supply valve 23, as'shownin Fig. 2.

V The cam depression 36 is ota length to regagement with the periphery of the wheel 5.

lVhile'the disc 43 is secured to the inner end of the shaft 42 to turn therewith, it is in reality carried by a stem 44 projected axially i from a socket in the inner end of the shaft 42 for axial movement therein. ,A springv 45 is mounted within `the shaft 42 and acts on the stein to effect an outward pressure thereon, thereby maintaining a closedriving contactof the disc 43 with thek wheel 5, and

also'exerting an outward pressure on the 'fand at its inner end on theshaft 41 for .turning movements relative thereto. Vvshell has, in the present instance,'a pulley 47 on its outer periphery to adapt it to be connecte-d to any suitable driving means and Vshaft 42.`

hollow shell 46 is mounted at its outer end on the outerv end portion of the shaft 42 ree This is provided interiorly with a vconical clutch surface 48-with whicha conical clutch wheel 49'fixed to the shaft-42interiorlyiot the shell Vis adapted to have frictional clutch engagement. .The end of the shaft 41 within the shell 46 is provided with -an annular flange ,'50 from which pins 51 project into sockets in the clutch wheel 49 and receive lthe outward thrust of springs 52 in said sockets.

A thrust bearing 53 is Vdisposed between the inner end of the shell 46y and flange 50. It is apparent that the clutch member 49 normally held in clutch engagement withthe shell or drive clutch member46 by .the action of the springs 52,

', as well as the spring 45.

` A lever 54 is fulcrumed to an upstanding part of the frame arm 3VO and has its upper i end-in thrust connection with the outer end of the shaft 42 through a link 55 and is provided atits lower end with a roller 56 Vwhich rides on the periphery ot the cam 28 and is held in engagement therewith by the outward thrust action on the shaft 42 of thc springs and 52. When the cam 28 is in Vthe normal position shown, the` roller 56 stands inadepressionv 57 in the cam, and immediately upon a movement of the cam from such normal position thel roller is abruptly forced outward, thereby rocking the lever 54 Aand forcing the shaft 42 inward to carry the clutch member 49 therewith vand 1 release it from driving engagement with the drive member 46. Y

In the'operation of the apparatus vit will be understood that when the control means,

1,617,5ael

for instance the arm 31, is in normal posiy tion the work-holding stem 9 will be rotated dueto the driving engagement ot' the. shell 46 with the clutch wheel 49 and the engagement of thedrive disc 43 with the wheel V5 on the spindle or shaft 4 of the work-holder, and at the same time the supply valve 23 Vwill be seated to close the communication between the interior ofthe cylinder 6 and source of vair, pressure supply, and the exhaust valve 20 Will be open, thereby permitting exhaust to take place from the lower portion of the cylinder 6 andy enabling the spring 8 to act to force the plunger 7 inward to effect a suction through the stem 9. l/Vhen it is desired to vremove the article@ from the holding stem 9 or to place an' article in holding engagement therewith, the

operator depresses the foot pedal 33, or

otherwise operates the control to effect, in the present instance, a vdownward movement of the arm 31 from normal position and a rocking of the cam 28. When this rocking takes place the cam shaft acts on the clutch control lever 54 to effect an inwardmovement of the shaft 42 and a consequent release of the driving engagement ot' the shell or clutch-member 46 with the clutch wheel 49, thereby stopping the rotation of the work-holder. r [`he cam 28 next acts,'up on a predetermined further rocking movement thereof, to move the air control lever 26 to permit a closing of the exhaustvalve20 and effect an opening of the air supply valve 23, thereby `closing the exhaust trom the cylinder 6 and opening communication between it and the source of air pressure supply. When such latter communication is'opened, the air yunder-pressure enters the cylinder 6 and forces the plunger 7 outward against the tension of they spring 8, thereby releasing the suction force through the stem 9, which holds an article seated on. the vcup 10 and permits the article tombe-removed. lV hen another article to be operated on has been placed in proper holding position on the cup 10, the operator releases the control means, thereby permitting it to return to the normal position shown in Fig. 1, vwhich return first closes the air pressure supply valve 23 and opens the exhaust valve 20, thereby permitting the spring Sto force the`plunger 7 inward and effect a pneumatic holding action on the article. This having been accomplished, lclutch parts are permitted to return to their normal positions to efl'ect a driving oi the rotatable parts'.

If there is any leakage within the suction portion of the cylinder 6, which would tend to relieve the suction action on the article and thereby raise itfrom the spindlewhen being rotated or operated on, such leakage is compensated for by the action of the spring 8, which continues Y to force the plunger outward to the limit of its per- Cil missible stroke and thereby prolong for some time the constant aiticle-holding suction within the stem 9, even though considerable leakage may occur. For this purpose the initial movement of the plunger' 7 in creating an article-holding suction through the stem 9 is only a portion of its full stroke, as illustrated in Fig. l.

I wish it understood that my invention is not limited to any specitic construction, arrangement or form ot the parts as it is capable of embodiments in numerous forms without departing from the spirit olI the claims. v

Having thus described my invention, what I claim as new and desire to secure by Letters Pat-ent is:

l. ln combination with a Yvacuum actuated work holder, a disconnectible means to rotate the holder, means to supply air to the work holder to release the work including a pair of self closing valves, one operating to admit the air to release the work, andthe ther operating to exhaust the chuck-rcleasing pressure, a lever pivoted intermediate said valves adapted to contact alternately therewith, and a single means for successively first disconnecting the rotating means and then engaging the lever for operating the air supplying means whereby to initially disconnect the rotating means and to subsequently operate the air supplying means to release the Work holder.

2. In combination with a vacuum actuated work holder, discoiinectible means to rotate the holder, means to supply air to the work vholder to release the work including a pair of valves, a lever pivoted intermediate said valves adapted to contact alternately there- Ywith to supply and exhaust therair to the work-holder, and cam Vactuated means' for both disconnecting the rotating means and for operating the` air supplying means whereby to initially disconnect the rotating means and to subsequently operate the air supplying means to release the Work holder.

3. In combination with a vacuum actuated work holder, disconnectible means to rotate the holder, means to supply air to the work holder to release the work, and a single means tor both disconnecting the rotating means and for operating the air supplying means, including a pair ot' pivoted levers,

and cam means interposed between the ad-,

initiall" disconnect the rotating means and Y J ri to subsequently operate the air supplying means to releasevthe work-holder.

In testimony whereof I have hereuntosigned my naine to this s ecilication.

FRAN A. BAILEY. 

